Systems for controlling the movement of barriers, such as upward acting sectional or single panel garage doors, rollup doors, gates, and other types of motor operated barriers, utilize remotely controlled barrier operators for effecting the requisite control. The remote control of the barrier operator is typically provided by user-actuation of interior or exterior building mounted consoles, in wired or wireless communication with the barrier operator, as well as by remotely located hand held or vehicle mounted wireless transmitters, transmitting barrier movement commands, typically access code encrypted, to the barrier operator. A microprocessor or microcontroller based controller unit associated with the barrier operator receives and decrypts these encrypted commands, and based thereon, instructs an associated motor to respectively open, close, halt the travel of, or otherwise move, the barrier in accordance with the transmitted commands.
The wireless transmissions are typically in the form of radio frequency (RF) transmitted data packets, the data packets thereafter received by an appropriately tuned RF receiver associated with the barrier operator, where they are then decoded and processed by the barrier operator controller. A typical RF communication protocol now in use by the industry adopts code-hopping encryption of the access codes, sometimes referred to as “rolling codes”, to prevent capture of the access codes by those not authorized to control the barrier operator.
Various drive assemblies are used to move the garage door or other barrier in accordance with the instructed operation. For example, it is typical in garage door installations for an AC or DC motor to reciprocatingly drive a coupled screw, belt or chain to correspondingly move a carriage interconnected with the garage door back and forth along a building mounted rail, thereby moving the door in the respectively instructed direction. The barrier operator, directing the motor shaft to turn in one direction or the other, thus causes the door to be moved by the drive assembly along a pair of oppositely disposed curved tracks between a fully vertical (closed) position and a fully horizontal (open) position. A large compression spring, along with associated pulleys and trained cables connected to the door, provide assistance to the door opening and closing operations.
Various techniques are also known to those of ordinary skill in the art for electronically setting the open and close travel limits of the carriage as well as electronically establishing the force sensitivity limits. The electronically set force sensitivity limits determine the upper limits of the force to which the door can be subjected as it travels along its path before there is an indication of an obstruction. Exceeding these limits then typically results in either the stoppage, or the stoppage and reversal, of the motor (and thus the door travel), respectively depending upon the door's then existing direction of travel.
While the past years have witnessed increased sophistication in the design and operation of these barrier operator systems, the present systems are not entirely satisfactory for all conditions of service. Consequently, it is the principal object of the herein described inventions to provide such improvements and additions to existing barrier operator systems, particularly in the area of a new and improved mechanical drive sub-system as well as to the electronics and software controls thereof, so as to provide improved operating characteristics of the resulting systems.